How to mock a socket connection in a test ?

[ValentinVignal]

I have a production code that looks like that:

final socket = io('/my-url')..connect();

socket.on('myEvent', myCallback);

test('', () {
   // I want to trigger 'myEvent' so `myCallback` is executed.
});

Looking around in the code, I saw that when a Socket is created, it creates a Transports.newInstance, which in the case of the test, uses the io implementation in io_transports.dart and returns an IOWebSocketTransport. It then creates a WebSocket.connect from dart:http which uses in the end HttpClient from dart:http.

HttpClient can be mocked tests using HttpOverrides.runZoned.

Is it possible to provide an example of how to mock the HTTP client or anything else to write tests?

[magamal]

any updates?